Using an EBT card requires no photo ID, which makes them open to fraud. A recipient can report a card lost or stolen and still receive his or her food stamp benefits.

The Department of Agriculture, the federal agency that oversees the Supplemental Nutritional Assistance Program (SNAP), sent letters in 2012 to Craigslist, eBay, Facebook, and Twitter reinforcing that buying and selling EBT cards is illegal and asking them to remind customers.

Craigslist prohibits the sale of food-stamp cards, and removes ads with them, but only if someone reports them.

In 2012, states were given more authority to investigate those who made multiple requests for card replacements. Anyone who requests more than four replacements a year is investigated and could be removed from the program.

Food-stamp fraud costs the government an estimated $750 million per year, about 1 percent of the program's total budget.

"The U.S. Department of Agriculture has zero-tolerance for SNAP fraud," a USDA spokesman told FoxNews. "We recently provided stronger tools to help state agencies — responsible for pursuing recipient fraud — crack down on individuals attempting to sell benefits online.

"In addition," he said, "since 2011, we have worked with online marketplaces, including Craigslist, to better monitor and put a stop to the illegal sale of SNAP benefits."